1. Field of the Invention
The present invention relates to a cylinder head and a head gasket, and more particularly to a cylinder head and a head gasket for preventing leaking of combustion gas and coolant.
2. Description of Related Art
As shown in FIG. 1, an engine for a vehicle includes a cylinder head 101 and a cylinder block 103, and a head gasket 105 is interposed between them.
The cylinder head gasket 105 sustains air-tightness between the cylinder block 103 and the cylinder head 101, and simultaneously prevents leaking of coolant and engine oil that is supplied to the engine.
As shown in FIG. 2, a gasket attachment surface is formed in a lower surface of the cylinder head 101.
The bolt boss portion 120 in which a head bolt is inserted is separated from the edge circumference portion 130 of the waterjacket WJ in the cylinder head 101 as shown in FIG. 2.
Furthermore, as shown in FIG. 3, a beading portion B having a single bead is formed in the cylinder head gasket 105 corresponding to the gasket attachment surface of the cylinder head 101 and the cylinder block 103.
Additionally, in this conventional art, an engagement force of a head bolt assembled through the bolt boss portion 120 is not sufficiently applied to the portion in which a coolant inlet portion P of the cylinder head 101 is formed due to the large space of the coolant inlet portion P, and so it is hard to correspond to the maximum pressure of the cylinder.
That is, the engagement force of the head bolt is not uniformly transferred to the vicinity of the coolant inlet portion P such that the attachment force is lowered.
Further, a crack occurs to the cylinder head gasket 105 due to deformation of the cylinder head gasket 105, and thus combustion gas, coolant, and oil can leak through the crack.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.